HR 4458

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HR 4458 A/B
Observation data
Epoch J2000
Constellation
(pronunciation)
Hydra
Right ascension 11h 34m 29.4871s
Declination -32° 49′ 52.823″
Apparent magnitude (V) 5.98/15
Characteristics
Spectral type K0 V
U-B color index 0.33
B-V color index 0.80
V-R color index 0.44
R-I color index 0.40
Variable type None
Astrometry
Radial velocity (Rv) -22.6 km/s
Proper motion (μ) RA: -670.99 mas/yr
Dec.: 823.89 mas/yr
Parallax (π) 104.84 ± 0.81 mas
Distance 31.1 ± 0.2 ly
(9.54 ± 0.07 pc)
Absolute magnitude (MV) 6.09/15
Details
Radius 0.84/0.15[1] R
Surface gravity (log g) 4.6[2]/–
Temperature 5400[2]/2960[1] K
Metallicity [Fe/H] = -0.26[2]
Other designations
Database references
SIMBAD data
ARICNS data

HR 4458 is a binary star system in the constellation Hydra. At a distance of 31 light years, they are the closest stars to the solar system within this constellation. The pair have an angular separation of 16.2″.[3]

[edit] References

  1. ^ a b Johnson, H. M. & Wright, C. D. (183). "Predicted infrared brightness of stars within 25 parsecs of the sun". Astrophysical Journal Supplement Series 53 (2): 643–711. doi:10.1086/190905. 
  2. ^ a b c Flynn, C.; Morell, O. (1997). "Metallicities and kinematics of G and K dwarfs". Monthly Notices of the Royal Astronomical Society 286 (2): 617–625. 
  3. ^ Poveda, A.; Herrera, M. A.; Allen, C.; Cordero, G.; Lavalley, C. (1994). "The new astrometry". Revista Mexicana de Astronomia y Astrofisica 28: 43–89. 

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